The machining properties of some hardwoods and softwoods naturally grown in Eastern Black Sea Region of Turkey

Abstract

This study is carried out on the machining properties (planing, shaping, turning, boring, mortising and sanding) of naturally grown Oriental beech ( Fagus orientalis Lipsky.), Anatolian chestnut ( Castenea sativa Mill.), Black alder ( Alnus glutinosa subsp. Barbata (C.A.Mey.) Yalt.), Scots pine ( Pinus sylvestris L.) and Oriental spruce ( Picea orientalis (L.) Link.) in the Eastern Black Sea Region of Turkey according to ASTM D 1666–87. In the test, a total of 25 sample trees 5 and replicate for each tree species are randomly selected from optimal grown areas of these species. Logs with 1.30 m length are taken from the trunk at a height of 2.5–5.5 m. Test specimens prepared from the lumber cut tangentially from logs are machined at 12% moisture content using different tools, and surface quality obtained is visually graded on a scale of 1–5 (excellent or defect free to very poor). Machining properties are determined to be excellent and good for all tree species except for the Norway spruce, which is graded good and fair. Moreover, for planing, the best surface quality is obtained generally at a somewhat low degree of rake angle (15°–20°) for hardwood, and a little high degree of rake angle (15°, 20° and 25°) for softwoods. In the same way, the best machining performance is at high feed speed or few cutting marks (15–20 per 25 mm length) for Oriental beech, and is at somewhat low feed speed or relatively more cutting marks (20) for the other species.